Mix the butter and flour together to form a very loose and crumbly dough.

Separate all 5 eggs (if you've never done this before - basically you open the egg over a bowl and pass the yolk back and forth to the two halves of shell, allowing the whites to fall into the bowl and placing the yolks in a separate bowl). (one yolk broke, so ignore that it only looks like 4 yolks)

Add the yolks to the flour mixture, and set the whites aside. Add sugar according to taste. Zest one lemon and add the zest and juice.

Mix the dough again so that everything is of even consistency - it should be flaky, but able to form balls when squeezed. Take two large pans or cookie sheets (or one ginormous oven pan like I've done) and press the dough firmly onto the pans about 1 cm thick, rolling out as necessary (do not grease the pans - the pound of butter in the dough makes it come off easily on its own!).

Leave one baseball-sized portion of dough behind. Take a long sheet of saran wrap (cling film) and place the extra dough on one end, folding the saran wrap over it.

Roll the dough ball until about 1/2 cm thick.

Back to the main pans - spread the jam evenly over each pan. If it's a firmer jam you can get away with a thicker amount, but if it's quite thin like a lot of apricot jams, be careful not to overload it (you'll probably use most of each jar, but probably not all of it). In our family, the jelly bars always had two different flavors - one was always apricot and that side always got the meringue topping. The second flavor was usually strawberry but sometimes changed according to my grandma's whims. I have chosen wild blueberry jam because it's my absolute favorite flavor. I would think that any kind of jam would work in these bars so go with what you like.

Take the extra rolled dough and cut into 1 cm wide strips with a pizza cutter.

Lay these strips over one pan of dough (in my case, the blueberry side) in a trellis pattern.

For the other pan (apricot), add a teaspoon of sugar to the egg white and beat with an electric mixer until stiff peaks form.

Stiff peaks formed:

Spread this meringue over the other pan.

Sprinkle both pans with finely crushed walnuts. Since my food processor was messy from the meringue, I used my DIY crushed walnut route - place a handful of walnuts in a sandwich bag, press out all the air, and then smash with a tin of vegetables or a heavy mug.

Shake out the walnuts evenly.

Evenly distributed walnuts:

Bake in a "slow oven" - about 300F/150C - for about an hour. After an hour, trim about two inches from around the edges of the pans and cut into square bars.

Set these edge bars aside to cool, and sprinkle with powdered sugar. Return the pans with the centers to the oven for approximately 20 more minutes, or until the base is firm but not hard. Cut into bars as before and sprinkle with powdered sugar.

Finished bars will have a soft, flaky, lemon-hinted crust with gooey jam and crunchy walnuts on top. It's a texture sensation for your mouth, with the added fun of a lighter-than-air meringue topping on the apricot side.

Now that you have learned how to make mima’s hungarian jelly bars, please be sure to view these other pastry recipes. Also, you will love these Eastern European recipes.